Both tamoxifen and toremifene have side effects. The indications for the drugs are different, and the side effects vary from person to person, so it is not possible to generalize, and therefore it is not possible to scientifically compare the size of the side effects, and it is recommended to choose the right drug under the guidance of a professional doctor. 1. Tamoxifen: Adverse effects include vaginal bleeding, menstrual disorders, vaginal discharge, rash, herpetic eruption, erythema multiforme, headache, solid pneumonitis, allergic reactions, elevated serum triglyceride levels, endometrial cancer, pulmonary embolism, stroke, cataract, thrombocytopenia, increased bone pain, amenorrhea, and so on. Tamoxifen is mainly used for the treatment of recurrent metastatic breast cancer in women, adjuvant treatment of metastasis after breast cancer surgery and prevention of recurrence. It is contraindicated in patients who are allergic to this product. It is contraindicated in patients treated with coumarin anticoagulants or patients with a history of pulmonary embolism, deep vein thrombosis, and those with fundus disorders. 2. Toremifene: Adverse reactions include flushing, sweating, nausea, dizziness, edema, vomiting, vaginal bleeding, increased vaginal discharge, fatigue, somnolence, depression, transient ischemic attack, vertigo, tremor, stroke, paralysis, arthritis, pulmonary embolism, asthenia, dyspnea, myocardial infarction, angina pectoris, cataract, glaucoma, dermatitis, hair loss. Toremifene is primarily used for the treatment of metastatic breast cancer in postmenopausal women with estrogen receptor-positive or unknown estrogen receptors. It is contraindicated in patients who are allergic to the product. It is prohibited for patients with hypokalemia, hypomagnesemia, prolonged QT interval, etc. It is recommended that patients who are unwell go to regular hospitals for consultation and follow the doctor’s instructions for symptomatic treatment.